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seeking I saw Jupiter, Venus, and some other luminaries. A portion of this light may have proceeded from the reflection of a thunder cloud, a short distance from and feebly lighted by the Sun. I give the result of the observations made with the thermomultiplier of Melloni by M. Botella, inspector of mines. In general the progress was very regular, as the figures show :
A very sensitive declinometer of Jones, observed hourly by M. Mayo, engineer, showed no disturbance. Professor Barreda observed the solar spectrum at my request, and will give his report thereon in a special Isles I’. 4. On the polarization of the light of the corona, and of the red protuberances, in total solar eclipses.—M. PRAZMowsRI observed at Briviesca in Spain, with special reference to these subjects, the total eclipse of July 18th. His observations seem to justify the following conclusions, viz. (1.) The light of the red protuberances is not polarized. In this respect they resemble clouds in our atmosphere. May we hence conclude that these are solar clouds, composed of particles, not gaseous, but liquid or even solid 3 The high temperature of the sun leads us to infer that these clouds are constituted of very refractory matter. (2.) The polarization of the corona proves that its light emanated from the sun and was reflected. The bright, very decided, polarization, proves also that the gaseous particles from which it was reflected send the light to us reflected nearly at the maximum angle of polarization. For a gas this angle is 45°; but in order to reflect light at this angle it must be near the sun. A solar atmosphere seems to furnish the necessary conditions—Comptes Rendus, Août 6, 1860, 5. Baily's Beads.-MR. LESPIAULT, who watched especially for this phenomenon, says—(Compt. Rend, li, 221)—some seconds before the first interior contact, the margin formed by the arc of the moon appeared irregular and trembling, but I did not see either the “BailyBeads” or “comb-teeth.” 6. Third Comet of 1860–A brilliant comet, with a tail several degrees long, was seen by many persons in different parts of our country, on the evening of June 21st and 22d, 1860. It was seen on the evening of June 20th, by Prof. Caswell of Providence, then on the deck of the steamship Arabia. The first public notice of the comet appears to have been made by Mr. C. W. Tuttle, assistant in the Harvard College Observatory. The comet continued vissible to the naked eye about two weeks.
The following parabolic elements of its orbit were computed by Mr. Tuttle, from observations at Cambridge, Mass, of 21st, 24th and 27th of June.
Perihelion passage, 1860, June 16.06730.
Long, of perihelion, - * - 161° 34' 56" | Mean eqx. “ “ asc. node, - * - 84 41 20 s Jan. 0.
Inclination, -> e- - - 79 18 11
Log. of perihelion distance, - 9.46687
Motion, - - so o - direct,
Gould's Astron. Jour, No. 136.
7. The Meteor of July 20th, 1860.-This remarkable meteor was visible over a portion of the earth's surface at least a thousand miles in length (from N. N. W. to S. S. E.) by seven or eight hundred in width; or from Lake Michigan to the Gulf Stream and from Maine to Virginia. The newspapers have contained many notices of its appearance as seen at various places within these limits, but most of these accounts are too vague to be of any scientific value. We are not yet in possession of a sufficient number of good observations for a final discussion of the phenomena presented, and can only at this time notice briefly a few of the best that have come to hand, and state some approximate results derived from them respecting the height of the meteor above the earth, the direction of its path, &c. At New Haven, it was seen, during a portion of its flight, by several members of the Scientific Faculty of the College at the house of Prof. J. A. Porter, and pains were at once taken to fix its apparent path by reference to parts of the building, tree-tops, stars, &c., near which it had been seen, and also to determine its time of flight, by noting the time required to repeat the various acts performed while it was in sight. The bearings and altitudes of the points noted for fixing the path were subsequently determined instrumentally. Independent data of the same kind were also obtained by going with many different observers to the places occupied by them at the time, and observing with compass and quadrant the path in the sky pointed out by each, and noting the time for each in the manner already indicated. By laying down these bearings and altitudes on a globe, a normal or average path was obtained, which cuts the horizon at N. 62° W. and S. 62° E., and gives a maximum altitude of 53°, in a direction S. 28° W. The time of flight for the different observers, determined as above stated, ranged from 10 to 20 seconds—giving an average of fourteen or fifteen seconds, which agrees with the careful estimate made at the time by the observers at Prof. Porter's. Valuable observations have also been received from individuals in different places, some items of which we proceed to state. They will be given more fully hereafter. Mr. J. D. Lawson, of New York, saw the meteor from the corner of Fourth street and Broadway, and has furnished data which give for maximum altitude (N.) 56%". Another independent observation at the same spot, as published in the Journal of Commerce, gives from data subsequently obtained by Prof. H. A. Newton, an altitude of about 55°. We use for N. Y. 56° as the mean of the two.
Mr. F. Huidekoper, of Meadville, Pa., makes the altitude at that place 39° 30' from the northern horizon; the point of disappearance at altitude 3° 30', and 10° 45' S. of east; time from crossing meridian till disappearance, 10 to 12 seconds. Mr. W. King, a surveyor at Erie, Pa., makes the altitude 44°, and point of disappearance in a cloud due east at an altitude of 22°. Mr. S. B. McMillan, of E. Fairfield, Ohio, reports it as having been seen “moving from a point about 10° E. of N. to within as much of a due east direction,” attaining an altitude of 15°. Rev. T. K. Beecher at Elmira, N. Y., saw it pass very nearly through his zenith, and “so very close to” or Lyrae “as to quench, if not eclipse it.” This star was then about 11° from his zenith, and in azimuth S. 764° E. The meteor separated into two parts with an explosion when near the zenith. Other observations (not now at hand), which have been used in obtaining our results, have been received from Mr. B. W. Marsh, of Philadelphia, and Prof. Hallowell, of Alexandria. A comparison of these observations, and a few of the best that have been published, give approximate results as follows: (1.) The vertical plane in which the meteor moved cuts the earth's surface in a line crossing the northern part of Lake Michigan, passin through, or very near to, Goderich on Lake Huron, (C. W.), Buffalo, Elmira and Sing Sing, N. Y., Greenwich, Conn., and in the same direction across Long Island into the Atlantic. (2.) In this plane the path that best satisfies the observations is sensibly a straight line approaching nearest to the earth (41 miles) at a point about south of Rhode Island, and having an elevation of 42 miles above Lon Island Sound, of 44 over the Hudson, 51 at Elmira, 62 at Buffalo, 85 over Lake Huron, and 120 over Lake Michigan. The western observations, however, which are few and imperfect, seem to indicate a somewhat greater elevation than this for the western part of the path. Possibly, therefore its true form may have been a curve convex towards the earth, resulting from the increasing resistance of the atmosphere as the meteor descended into denser portions of it. The observations made this side of Buffalo, which are somewhat numerous and many of them good, are very well satisfied by the straight path already described. Further and more accurate observations beyond Buffalo are greatly needed for determining the true form and position of the orbit, both in respect to the earth's surface and in space. (3.) The close approximation to parallelism to the earth's surface of the eastern portion of the observed path leaves it a matter of doubt, considering the imperfection of the observations, whether the meteor finally passed out of the atmosphere and went on its way in a disturbed orbit, or descended gradually into the Atlantic. The former supposition is perhaps the more probable, especially if the path was curved, as above suggested, instead of a straight line. (4.) The meteor exhibited different appearances in different parts of its course. It seems to have been observed first as a single body, more or less elongated, gradually increasing in brilliancy, throwing off occasionally sparks and flakes of light, until it reached the neighborhood of Elmira, N.Y. Here something like an explosion occurred, and the meteor separated into two principal portions with many subordinate fragments all continuing on their course in a line behind each other, and still scattering luminous sparks along their track, until a point was reached about south of Nantucket, when a second considerable explosion took place, and afterwards the principal fragments passed on till lost to view in the distance. The most trustworthy observations represent the meteor as disappearing while yet several degrees above the horizon, (generally from 8° to 6° or 8°). Besides the actual changes of form which the body successively underwent, apparent changes would present themselves to each observer arising from change of direction in which the meteor was seen. (5.) It is not easy, from the observations in hand, to determine with much accuracy the velocity of the meteor while passing through our atmosphere. The time of flight is doubtless largely overestimated by most observers, especially those unaccustomed to measure intervals of a few seconds. Timing with a watch a repetition of the acts performed during the flight of the meteor, usually reduces the interval to not more than one third, or even one fifth, of the observer's own estimate. From 15 to 30 seconds is a fair range for good observations, and probably to no observer was the meteor in sight over 45 seconds or a minute, although a minute and a half and two minutes are very common estimates. A comparison of the most probable estimates of time with the length of path observed, gives a velocity ranging from eight to fifteen miles a second. Probably 12 or 13 miles is a tolerable approximation. This, allowing for the earth's motion in its orbit, gives 26 or 27 miles a second as the actual velocity of the meteor in space. Its relative velocity may have been much greater when just entering the atmosphere, than after encountering its accumulated resistance. (6.) The actual diameter of the luminous mass, taking its apparent diameter as nearly equal to that of the moon, (the estimate of many observers nearest its track) must have been from one-fifth to one-third of a mile. Many estimates would make it still larger. The two principal heads when passing New Haven must have been from one to three miles apart. (7.) A report is mentioned by many observers as having been heard from one and a half to five minutes after the meteor passed. The least time in which such a report could have been heard, taking the usual constant for the velocity of sound (1090-47 feet a second) would be about three minutes and a half. This is a point of much interest, and needs to be investigated. The “rushing sound” spoken of by many as heard while the meteor was passing, is of course to be attributed to imagination. C. S. LYMAN. 8. The Meteors of August 2d and 6th, 1860—A meteor, rivaling in brilliancy that of July 20th, was extensively observed throughout the Southern United States on the evening of August 2d, between 10 and 11 o'clock, according to the local time. It appears to have passed from east to west vertically over Tennessee at ten minutes past ten, Knoxville time. “From three to five minutes after the disappearance of the meteor a report was heard like the discharge of an eight-pounder; which was followed by a long—long rolling, reverberatory sound of more than a minute's duration.” This fact is mentioned by Mr. W. C. Kane writing from Knoxville to a friend in Hartford, Conn. Another brilliant meteor was seen in the Southwest, from New Haven and New York, between half past seven and eight o'clock, on the evening of August 6th. It passed from south to north, and notwithstanding the daylight still remaining attracted attention over a wide extent of country. 9. Further Wotice of the Wew Concord (Ohio) Meteor, of May 1, 1860; by Prof. E. W. Evans—Since writing my communication published in the July number of this Journal, on the path and height of the New Concord meteor, I have found some additional data, which I regard as important because they have been furnished by a good observer who saw the meteor under favorable circumstances. A single case of this kind is the more worthy of note because, owing to the cloudiness of the day when this meteor passed, there were but a few places from which it was seen at all. The observer referred to is D. Mackley, Esq., a lawyer of Jackson, Ohio, who at the time of the occurrence happened to be at Berlin, about six miles north east from the former place, and seventy miles from the nearest point under the meteor's path. He took pains to note all the facts as accurately as he could at the time; and he afterwards returned to the spot in order to determine more definitely the points of the compass. His testimony, in answer to my interrogatories, is substantially as follows:— “The meteor first appeared to me at a point about 55° east of north. It moved northward in a line very nearly parallel with the horizon. When it disappeared it had described an arc of about 15°. It was in sight about 6 seconds. Its altitude was about 30°. In regard to its size, I have since looked at the sun through a thin cloud, and I think the apparent diameter of the meteor was one-half that of the sun.” These data give the meteor a height of 41 miles over the northern boundary of Noble county; a diameter of three-eighths of a mile; and a relative velocity of nearly 4 miles a second. The results agree sufficiently well with those before given. - - The meteor was seen through openings in the clouds at various points along a line of 60 miles, extending from near Newport on the Ohio river to the neighborhood of New Concord. The evidence, upon the whole, does not indicate any descent of the body towards the earth between these limits, or any change in its size or appearance. From this fact, and the great height of the body, and the absence of all evidence that it was seen or heard in the northern part of the State or beyond, it seems probable that this meteor was not dissipated in the atmosphere, but passed out of it again. The shower of stones which came down near New Concord had probably been detached from the principal mass before the latter came into sight. Marietta, Ohio, Aug. 20, 1860.
10. Shooting Stars of August 9–10, 1860–Since the year 1837, at least, it has been found in the Northern hemisphere, whenever the weather has permitted observation, that shooting stars have been unusually abundant during a period of several nights in August, gradually increasing in numbers for a few days up to the 10th of the month,